Field of the Invention
This invention generally relates to a bicycle pedaling force detector. More specifically, the present invention relates to a bicycle pedaling force detector having a wireless communicator is configured to be detachably connected to a crank assembly, and housed separately from a sensor circuit mounted to the crank assembly.
Background Information
Bicycles are sometimes equipped with various sensors for providing information to the rider and/or for providing information to a controller to control various aspects of the bicycle such as shifting or suspension stiffness. One such sensor is a torque or force sensor for detecting a pedaling force of the rider. Various sensing arrangements have been proposed for detecting a pedaling force of the rider. For example, in U.S. Pat. No. 7,516,677 (assigned to Shimano Inc.), a cylindrical torsion-detecting sleeve member (force sensor unit) is provided on a crank axle for detecting a pedaling force applied to the crank axle during pedaling.
Pedaling force detectors typically use strain gauges to measure pedaling force during pedaling. For example, a force sensor is disclosed in U.S. Patent Application Publication No. 2010/0282001 (assigned to Shimano Inc.), which utilizes a strain gauge for detecting a pedaling force applied to a crankshaft during pedaling. Recently, pedaling force detectors have incorporated wireless communication technology. For example, a pedaling force sensor is disclosed in U.S. Patent Application Publication No. 2012/0214646, which describes a power measurement device including processing circuitry within a housing. The processing circuitry is coupled with strain gauges mounted on the crank arm, and produces a power value that is wirelessly transmitted to a separate display that may receive and display power measurements. Some pedaling force detectors are arranged such that portions are disposed on a sensor board removable from a crank assembly, as disclosed in U.S. Patent Application Publication No. 2014/0060212 (assigned to Shimano).